Repo created

TMessagesProj/jni/voip/webrtc/base/debug/profiler.cc

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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/debug/profiler.h"
+
+#include <string>
+
+#include "base/allocator/buildflags.h"
+#include "base/debug/debugging_buildflags.h"
+#include "base/process/process_handle.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include "base/win/current_module.h"
+#include "base/win/pe_image.h"
+#endif  // defined(OS_WIN)
+
+// TODO(peria): Enable profiling on Windows.
+#if BUILDFLAG(ENABLE_PROFILING) && BUILDFLAG(USE_TCMALLOC) && !defined(OS_WIN)
+#include "third_party/tcmalloc/chromium/src/gperftools/profiler.h"
+#endif
+
+namespace base {
+namespace debug {
+
+// TODO(peria): Enable profiling on Windows.
+#if BUILDFLAG(ENABLE_PROFILING) && BUILDFLAG(USE_TCMALLOC) && !defined(OS_WIN)
+
+static int profile_count = 0;
+
+void StartProfiling(const std::string& name) {
+  ++profile_count;
+  std::string full_name(name);
+  std::string pid = NumberToString(GetCurrentProcId());
+  std::string count = NumberToString(profile_count);
+  ReplaceSubstringsAfterOffset(&full_name, 0, "{pid}", pid);
+  ReplaceSubstringsAfterOffset(&full_name, 0, "{count}", count);
+  ProfilerStart(full_name.c_str());
+}
+
+void StopProfiling() {
+  ProfilerFlush();
+  ProfilerStop();
+}
+
+void FlushProfiling() {
+  ProfilerFlush();
+}
+
+bool BeingProfiled() {
+  return ProfilingIsEnabledForAllThreads();
+}
+
+void RestartProfilingAfterFork() {
+  ProfilerRegisterThread();
+}
+
+bool IsProfilingSupported() {
+  return true;
+}
+
+#else
+
+void StartProfiling(const std::string& name) {
+}
+
+void StopProfiling() {
+}
+
+void FlushProfiling() {
+}
+
+bool BeingProfiled() {
+  return false;
+}
+
+void RestartProfilingAfterFork() {
+}
+
+bool IsProfilingSupported() {
+  return false;
+}
+
+#endif
+
+#if !defined(OS_WIN)
+
+ReturnAddressLocationResolver GetProfilerReturnAddrResolutionFunc() {
+  return nullptr;
+}
+
+AddDynamicSymbol GetProfilerAddDynamicSymbolFunc() {
+  return nullptr;
+}
+
+MoveDynamicSymbol GetProfilerMoveDynamicSymbolFunc() {
+  return nullptr;
+}
+
+#else  // defined(OS_WIN)
+
+namespace {
+
+struct FunctionSearchContext {
+  const char* name;
+  FARPROC function;
+};
+
+// Callback function to PEImage::EnumImportChunks.
+bool FindResolutionFunctionInImports(
+    const base::win::PEImage &image, const char* module_name,
+    PIMAGE_THUNK_DATA unused_name_table, PIMAGE_THUNK_DATA import_address_table,
+    PVOID cookie) {
+  FunctionSearchContext* context =
+      reinterpret_cast<FunctionSearchContext*>(cookie);
+
+  DCHECK(context);
+  DCHECK(!context->function);
+
+  // Our import address table contains pointers to the functions we import
+  // at this point. Let's retrieve the first such function and use it to
+  // find the module this import was resolved to by the loader.
+  const wchar_t* function_in_module =
+      reinterpret_cast<const wchar_t*>(import_address_table->u1.Function);
+
+  // Retrieve the module by a function in the module.
+  const DWORD kFlags = GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
+                       GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT;
+  HMODULE module = NULL;
+  if (!::GetModuleHandleEx(kFlags, function_in_module, &module)) {
+    // This can happen if someone IAT patches us to a thunk.
+    return true;
+  }
+
+  // See whether this module exports the function we're looking for.
+  FARPROC exported_func = ::GetProcAddress(module, context->name);
+  if (exported_func != NULL) {
+    // We found it, return the function and terminate the enumeration.
+    context->function = exported_func;
+    return false;
+  }
+
+  // Keep going.
+  return true;
+}
+
+template <typename FunctionType>
+FunctionType FindFunctionInImports(const char* function_name) {
+  base::win::PEImage image(CURRENT_MODULE());
+
+  FunctionSearchContext ctx = { function_name, NULL };
+  image.EnumImportChunks(FindResolutionFunctionInImports, &ctx, nullptr);
+
+  return reinterpret_cast<FunctionType>(ctx.function);
+}
+
+}  // namespace
+
+ReturnAddressLocationResolver GetProfilerReturnAddrResolutionFunc() {
+  return FindFunctionInImports<ReturnAddressLocationResolver>(
+      "ResolveReturnAddressLocation");
+}
+
+AddDynamicSymbol GetProfilerAddDynamicSymbolFunc() {
+  return FindFunctionInImports<AddDynamicSymbol>(
+      "AddDynamicSymbol");
+}
+
+MoveDynamicSymbol GetProfilerMoveDynamicSymbolFunc() {
+  return FindFunctionInImports<MoveDynamicSymbol>(
+      "MoveDynamicSymbol");
+}
+
+#endif  // defined(OS_WIN)
+
+}  // namespace debug
+}  // namespace base